When non-optimal welding parameters are set for laser radiation welding, welding defects may occur, which can lead to seam irregularities. Such irregularities may include incomplete penetration, humping (e.g., irregularities in the curvature of a weld bead), and holes. Observation of a welding process may enable the detection of various welding and seam defects. However, reliable detection of defects may be disrupted by process emissions, such as process plasma or thermal radiation from a metal vapor plume or result from a surface finish on the weld bead.